Git is usually setup to work with one account on a server which can be accessed by SSH.
SSH itself allows to setup the access to the whole git account on the server.
But this does not allow to declare read/write permissions on files or branches. It just gives everybody who is
added as user through SSH to access the account with the same rights.
This can be totally OK for small projects or working alone.
For an actual user management implementation another software is used like Gitea.
It is installed on the server and acts as middle ware between users and git.
APP | VERSION Linux/Ubuntu
RELATED TAGS git, server, remote, repository, users
QUESTIONS
How can I add a new user to my git server?
What do I need to do to add a new git user via ssh keys?
How can I manage users on git?